Base coupling structure of a height adjustable chair

ABSTRACT

A base coupling structure of a height adjustable chair, using a sleeve to connect an oil cylinder and a foot support of a height adjustable chair, the sleeve and the oil cylinder can be tightly embedded together by taking the advantages of having slightly different taper sizes and different elasticity of materials, and the sleeve is coupled with the foot support by a screwing base structure which can be dismantle, so the present invention not only can enhance the speed of the replacing the used oil cylinder, but also can protect the foot support from being damaged and allow a reduction in service cost of the height adjustable chair.

FIELD OF THE INVENTION

The present invention relates to a base structure of a height adjustablechair and, more particularly, to a coupling structure between an oilcylinder and a foot support of the base of a height adjustable chair.

BACKGROUND OF THE INVENTION

Please refer to FIGS. 1 and 2, the conventional height adjustable chaircomprises of a seat portion 1, an oil cylinder 2 and a foot support 3.The oil cylinder 2 includes an adjustable lever 2 c, an extensible rod 2a and a connecting post 2 b. The extensible rod 2 a is mountedunderneath the seat portion 1 by a suited base 4 and a plurality ofscrews 5. Both the connecting post 2 b and the foot support 3 having ataper correspondingly, so that the connecting post 2 b can be tightlyembedded into the foot support 3 by the slightly differences between thetaper sizes and the elasticity of the materials between the two.According to the above structure, users can activate the adjustablelever 2 c to elongate the extensible rod 2 a in response to the motionof the oil cylinder 2, so as to elevate the seat portion 1.

Therefore, the altitude of the seat portion 1 can be adjusted accordingto the height of different users. This kind of height adjustable chairis commonly used in beauty parlors and saloons, so that the altitude ofthe client can be adjusted in order to facilitate the process of thetreatment. Although the altitude of the seat portion 1 of theconventional height adjustable chair can be adjusted according to thedemand of the user, the oil cylinder 2 of the conventional heightadjustable chair is easily damaged by the over frequent adjustment.During the time of replacing the damaged oil cylinder 2 to a new one,one has to separate the link between the oil cylinder 2 and the footsupport 3 by strong force (the oil cylinder 2 and the foot support 3 aretightly embedded with each other). Therefore, the foot support 3 of theconventional height adjustable chair can be easily damaged during thereplacement of the used oil cylinder 2. Thus, causing an increase inservice cost of the conventional height adjustable chair and obviouslydoes not conform to the demand of services.

SUMMARY OF THE INVENTION

It is a primary object of the present invention is to provide a couplingstructure for the oil cylinder and the foot support of the heightadjustable chair, so as to enhance the convenience of replacing the usedoil cylinder without damaging the foot support.

In order to achieve the foregoing objects, the present inventionprovides a base coupling structure of a height adjustable chair of thepresent invention comprising an oil cylinder, a sleeve and a footsupport. The bottom of the oil cylinder has a connecting post and suchconnecting post has a taper. The sleeve having a receiving hole whichhas a larger outer circumference and a smaller inner circumference. Andthe size of the receiving hole corresponds to the size of the connectingpost of the oil cylinder. Thus, the connecting post of the oil cylindercan be tightly embedded into the receiving hole of the sleeve by takingthe advantages of having slightly different taper sizes and differentelasticity of materials. The foot support has a housing space, and theaperture of the housing space is slightly bigger than the sleeve, sothat there will be a gap between the sleeve and the housing space whenthey are coupled together. As a result, the foot support of the presentinvention can be easily separated from the sleeve, when the oil cylinderof the present invention is damaged, by taking the advantage of theimproved base coupling structure between the sleeve and the footsupport, not only the speed of the replacing action can be enhanced, butalso the foot support can be protected from damage, allowing a reductionin service cost of the height adjustable chair.

The foregoing, as well as additional objects, features and advantages ofthe invention will be more readily apparent from the following detaileddescription, which proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective exploded view of a conventional heightadjustable chair structure.

FIG. 2 is a schematic partly sectional view of a conventional heightadjustable chair.

FIG. 3 is a perspective exploded view of a base coupling structure of aheight adjustable chair of the present invention.

FIG. 4 is a schematic partly sectional view of a base coupling structureof a height adjustable chair of the present invention.

FIG. 5 is a perspective view of another coupling method between thesleeve and the foot support of the present invention.

FIG. 6 is a perspective view of an additional coupling method betweenthe sleeve and the foot support of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 3 and 4. The base coupling structure of a heightadjustable chair of the present invention comprises an oil cylinder 10,a sleeve 20 and a foot support 30. The bottom of the oil cylinder 10 hasa connecting post 101 and such connecting post 101 has a taper. Thesleeve 20 having a receiving hole 201 which has a larger outercircumference and a smaller inner circumference. And the size of thereceiving hole 201 corresponds to the size of the connecting post 101 ofthe oil cylinder 10, so that the largest aperture of the receiving hole201 is slightly bigger than the connecting post 101 and the smallestaperture of the receiving hole 201 is slightly smaller than theconnecting post 101. Thus, the connecting post 101 of the oil cylinder10 can be tightly embedded into the receiving hole 201 of the sleeve 20by taking the advantages of having slightly different taper sizes anddifferent elasticity of materials. The oil cylinder 10 can be tightlyembedded within the sleeve 20 because part of the aperture of theconnecting post 101 is bigger than the receiving hole 201. Furthermore,the oil cylinder 10 has a first positioning hole 102 and the sleeve 20has a second positioning hole 202 corresponding to the first positioninghole 102. After the connecting post 101 of the oil cylinder 10 istightly embedded within the receiving hole 201 of the sleeve 20, a pin40 can be inserted between the first positioning hole 102 and the secondpositioning hole 202 so as to enhance the stability between the tightlyembedded oil cylinder 10 and the receiving hole 201.

The foot support 30 having a housing space 301, the aperture of thehousing space 301 is slightly bigger than the sleeve 20, so that therewill be a gap between the sleeve 20 and the housing space 301 when theyare coupled together. And the sleeve 20 having a threaded hole 203, suchthreaded hole 203 is located at the bottom of the sleeve 20, and thehousing space 301 also having a perforation 303 located at the bottom ofthe housing space 301 corresponding to the position of the threaded hole203 of the sleeve 20. The perforation 303 passes through the footsupport 30 in order to allow a screw member 50 to go through theperforation 303 and then fasten into the threaded hole 203. Furthermore,the screw member 50 can be coated with an elastic buckle 70 and a gasket60, in order to enhance the stability of the screw member 50 during thefastening operation. As a result, the sleeve 20 and the foot support 30can be coupled together by the security of the screw member 50. Thebottom surface of the housing space 301 further has an extruded rod 304.The sleeve 20 has a concave hole 204 corresponding to the position ofthe extruded rod 304. The extruded rod 304 engaged with the concave hole204 after the sleeve 20 has been inserted into the housing space 301, soas to enhance the stability of the coupling state.

Please refer to FIG. 5 again, which shows another coupling methodbetween the sleeve 20 and the foot support 30. The outer circumferenceof the sleeve 20 having a first threaded structure 205, while thehousing space 301 of the foot support 30 having a corresponding secondthreaded structure 305. The sleeve 20 and the foot support 30 can befastened together through the coupling between the first threadedstructure 205 and the second threaded structure 305.

Please refer to FIG. 6 again, which shows an additional coupling methodbetween the sleeve 20 and the foot support 30. The outer circumferenceof the sleeve 20 having a plurality of first L-shaped extruded portions206, while the housing space 301 of the foot support 30 having aplurality of corresponding second L-shaped extruded portions 306. Thesleeve 20 and the foot support 30 can be firmly anchored togetherthrough the coupling between the first L-shaped extruded portions 206and the second L-shaped extruded portions 306.

As stated above, since the oil cylinder 10 of the present invention istightly embedded within the sleeve 20, and the sleeve 20 is coupled andis anchored with the foot support 30 by a screwing base structure whichcan be dismantle. Thus, when the oil cylinder 10 is damaged and needs tobe replaced, the foot support 30 of the present invention can be easilyseparated from the sleeve 20, then replace the sleeve 20 and the oilcylinder 10 altogether. To conclude, when the oil cylinder 10 of thepresent invention is damaged, by taking the advantage of the improvedbase coupling structure between the sleeve 20 and the foot support 30,not only the speed of the replacing action can be enhanced, but also thefoot support 30 can be protected from damage, allowing a reduction inservice cost of the height adjustable chair.

Although the invention has been explained in relation to its preferredembodiment, it is not used to limit the invention. It is to beunderstood that many other possible modifications and variations can bemade by those skilled in the art without departing from the spirit andscope of the invention as hereinafter claimed.

1. A base coupling structure of a height adjustable chair, comprising:an oil cylinder, the bottom of said oil cylinder having a connectingpost, said connecting post having a taper; a sleeve, having a receivinghole which has a larger outer circumference and a smaller innercircumference, and the size of said receiving hole is corresponding tothe size of said connecting post of said oil cylinder, so that saidconnecting post of said oil cylinder can be tightly embedded into saidreceiving hole of said sleeve; and a foot support, having a housingspace, said housing space is slightly bigger than said sleeve, so as toform a gap between said sleeve and said housing space when they arecoupled together, and allowing said foot support to be fasten into saidsleeve.
 2. The base coupling structure of a height adjustable chairaccording to claim 1, wherein said sleeve having a threaded hole, saidthreaded hole is located at the bottom of said sleeve, and said housingspace also having a perforation located at the bottom of said housingspace corresponding to the position of said threaded hole of saidsleeve, said perforation passes through said foot support in order toallow a screw member to go through said perforation and then fasten intosaid threaded hole, so that said sleeve and said foot support can becoupled together by the security of said screw member.
 3. The basecoupling structure of a height adjustable chair according to claim 2,wherein the bottom surface of said housing space further having anextruded rod, said sleeve further having a concave hole corresponding tothe position of said extruded rod, said extruded rod engaged with saidconcave hole after said sleeve has been inserted into said housingspace.
 4. The base coupling structure of a height adjustable chairaccording to claim 2, wherein said oil cylinder having a firstpositioning hole and said sleeve having a second positioning holecorresponding to said first positioning hole, after said connecting postof said oil cylinder is tightly embedded within said receiving hole ofsaid sleeve, a pin can be inserted between said first positioning holeand said second positioning hole.
 5. The base coupling structure of aheight adjustable chair according to claim 1, wherein the outercircumference of said sleeve further having a first threaded structure,while said housing space of said foot support further having acorresponding second threaded structure, said sleeve and said footsupport can be fastened together through the coupling between said firstthreaded structure and said second threaded structure.
 6. The basecoupling structure of a height adjustable chair according to claim 1,wherein the outer circumference of said sleeve further having aplurality of first L-shaped extruded portions, while said housing spaceof said foot support further having a plurality of corresponding secondL-shaped extruded portions, said sleeve and said foot support can befirmly anchored together through the coupling between said firstL-shaped extruded portions and said second L-shaped extruded portions.7. The base coupling structure of a height adjustable chair according toclaim 1, wherein the bottom surface of said housing space further havingan extruded rod, said sleeve further having a concave hole correspondingto the position of said extruded rod, said extruded rod engaged withsaid concave hole after said sleeve has been inserted into said housingspace.
 8. The base coupling structure of a height adjustable chairaccording to claim 1, wherein said oil cylinder having a firstpositioning hole and said sleeve having a second positioning holecorresponding to said first positioning hole, after said connecting postof said oil cylinder is tightly embedded within said receiving hole ofsaid sleeve, a pin can be inserted between said first positioning holeand said second positioning hole.